nvme-apple: add missing MODULE_DESCRIPTION()

make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/nvme/host/nvme-apple.o

Add the missing invocation of the MODULE_DESCRIPTION() macro.

Reviewed-by: Eric Curtin <ecurtin@redhat.com>
Reviewed-by: Sven Peter <sven@svenpeter.dev>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>